nuclear chemical engineering

NUCLEAR CHEMICAL ENGINEERING Second Edition Manson Benedict Professor Emeritus of Nuclear Engineering Massachusetts Institute of Technology Thomas H. Pigford Professor of Nuclear Engineering University of Gal$omia, Berkeley Hans Wolfgang Levi Hahn-Meitner-Institut fir Kernforschung Berlin and apL Professor of Nuclear Chemistty Technische Universitat Berlin McGraw-Hill Book Company New York St. Louis San Francisco Auckland Bogota Hamburg Johannesburg London Madrid Mexico Montreal New Delhi Panama Paris SHoPaulo Singapore Sydney Tokyo Toronto This book was set in Press Roman by Hemisphere Publishing Corporation. The editor was Diane D. Heiberg; the production supervisor was Rosann E. Raspini. Kingsport Press, Inc. was printer and binder. NUCLEAR CHEMICAL ENGINEERING Copyright 0 1981, 1957 by McCraw-Hill, Inc. All rights reserved. Printed in the United States of America. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. 5 6 7 8 9 0 KPKP 8 9 8 7 6 5 4 Library of Congress Cataloging in Publication Data Benedict, Manson Nuclear chemical engineering, (McGraw-Hill series in nuclear engineering) Includes bibliographies and index. 1. Nuclear engineering. 2. Nuclear chemistry. I. Pigford, Thomas H., joint author. 11. Levi, Hans Wolfgang, joint author. 111. Title. TK9350.B4 1981 621.48 80-21538 ISBN 0-07-004531-3 PREFACE The development of nuclear fssion chain reactors for the conversion of mass to energy and the transmutation of elements has brought into industrial prominence chemical substances and chemical engineering processes that a few years ago were no more than scientific curiosities. Uranium, formerly used mainly for coloring glass and ceramics, has become one of the world’s most important sources of energy. Thorium, once used mainly in the Welsbach gas mantle, promises to become a nuclear fuel second in importance only to uranium. Zirconium and its chemical twin hafnium, formerly always produced together, have been separated and have emerged as structural materials of unique value in reactors. New chemical engineering processes have been devised to separate these elements, and even more novel processes have been developed for producing deuterium, *’’ U, and the other separated isotopes that have become the fine chemicals of the nuclear age. The processing of radioactive materials, formerly limited mainly to a few curies of radium, is now concerned with the millions of curies of radioactive isotopes of the many chemical elements that are present in spent fuel discharged from nuclear reactors. The preceding introduction to the preface of the first edition of this book can still serve as the theme of this second edition. Since 1957 nuclear power systems have become important contributors to the energy supply of most industrialized nations. This text describes the materials of special importance in nuclear reactors and the processes that have been developed to concentrate, purify, separate, and store safely these materials. Because of the growth in nuclear technology since the first edition appeared and the great amount of published new information, this second edition is an entirely new book,.following the first edition only in its general outline. Chapter 1 lists the special materials of importance in nuclear technology and outlines the relationship between nuclear reactors and the chemical production plants associated with them. Chapter 2 summarizes the aspects of nuclear physics and radioactivity that are pertinent to many of the processes to be described in later chapters. Chapter 3 describes the changes in composition and reactivity that occur during irradiation of fuel in a nuclear reactor and shows how these changes determine the material and processing requirements of the reactor’s fuel cycle. Chapter 4 describes the principles of solvent extraction, the chemical engineering unit operation used most extensively for purifying uranium, thorium, and zirconium and reprocessing irradiated fuel discharged from reactors. Chapters 5, 6, and 7 take up uranium, thorium, and zirconium in that order. Each chapter discusses the physical and chemical properties of the element and its compounds, its natural occurrence, and the processes used to extract the element from its ores, purify it, and convert it to the forms most useful in nuclear technology. X iii xiv PREFACE The next four chapters take up processing of the highly radioactive materials produced in reactors. Chapter 8 describes the isotopic composition and radioactive constituents of spent fuel discharged from representative types of reactors and deals briefly with other radioisotopes resulting from reactor operation. Chapter 9 describes the physical and chemical properties of the synthetic actinide elements produced in reactors: protactinium, neptunium, plutonium, americium, and curium, and their compounds. Chapter 10 describes the radiochemical processes that have been developed for reprocessing irradiated fuel to recover uranium, plutonium, and other valuable actinides from it. Chapter 11 describes conversion of radioactive wastes from reactor operation and fuel reprocessing into stable forms suitable for safe, long-term storage, and systems to be used for such storage. The last three chapters deal with separation of stable isotopes. Chapter 12 lists the isotopes of principal importance in nuclear technology, discusses their natural occurrence, and develops the chemical engineering principles generally applicable to isotope separation processes. Chapter 13 describes processes useful for separating deuterium and isotopes of other light elements, specifically distillation, electrolysis, and chemical exchange. Chapter 14 describes processes used for separating uranium isotopes, specifically gaseous diffusion, the gas centrifuge, aerodynamic processes, mass and thermal diffusion, and laser-based processes. Four appendixes list fundamental physical constants, conversion tables, nuclide properties, and radioactivity concentration limits for nuclear plant effluents. As may be seen from this synopsis, this text combines an account of scientific and engineering principles with a description of materials and processes of importance in nuclear chemical technology. It aims thus to serve both as a text for classroom instruction and as a source of information on chemical engineering practice in nuclear industry. Problems at the end of each chapter may prove useful when the text is used for instruction. References are provided for readers who wish more details about the topics treated in each chapter. Extensive use has been made of information from the Roceedings of the four International Conferences on the Peaceful Uses of Atomic Energy in Geneva, Switzerland, sponsored by the United Nations, which are listed as PIG, followed by the number of the conference, in the references at the ends of chapters. This book was written in a transition period when U.S. engineering and business practice was changing from English to SI units. When the references cited used Enash units, these have been retained in the text in most cases. Equivalent SI values are also provided in many passages, or conversion factors are given in footnotes. In addition, conversion tables are provided in App. B. The multiplicity of units is regrettable, but it is unavoidable until the world’s technical literature has changed over completely to the SI system. In preparing this text the authors have been blessed with assistance from so many sources that not all can be mentioned here. We are grateful to our respective institutions, Massachusetts Institute of Technology, University of California (Berkeley), and Hahn-Meitner-Institut (Berlin), for the freedom and opportunity to write this book. For help with calculations, illustrations, and typing, thanks are due Marjorie Benedict, Ellen Mandigo, Mary BOSCO, Sue Thur, and many others. Editorial assistance from Judith B. Gandy and Lynne Lackenbach is acknowledged with gratitude. To the many generations of students who used the notes on which this book is based and helped to correct its mistakes we are greatly indebted. Among our more recent students we wish to thank Men Croff, Charles Forsberg, Saeed Tajik, and Cheh-Suei Yang. Among our American professional colleagues we are greatly indebted to Don Ferguson and his associates at Oak Ridge National Laboratory; Paul McMurray and others of Exxon Nuclear Company; James Buckham and Wesley Murbach of Allied General Nuclear Services; James Duckworth of Nuclear Fuel Services, Inc.; Joseph Megy of Teledyne Wah Chang Albany Company; Paul Vanstrum and Edward Von Halle of Union Carbide Corporation; Lombard Squires, John PREFACE xv Proctor, and their associates of E. I. duPont de Nemours and Company; Marvin Miller of MIT; and Donald Olander of the University of California (Berkeley). In Germany, we wish to thank Hubert Eschrich of Eurochemic, Richard Kroebel of Kernforschungszentrum Karlsruhe, Erich Merz of Kernforschungsanlage Jiilich, Walther Schuller of Wiederaufarbeitungsanlage Karlsruhe, and Eckhart Ewest of Deutsche Gesellschaft fur Wiederaufarbeitung von Kernbrennstoff. Assistance provided to one of the authors (MB) by a fellowship from the Guggenheim Foundation is acknowledged with gratitude. Despite the valued assistance the authors have had in preparing this text, it doubtless still contains many errors and omissions. We shall be grateful to our readers for calling these to our attention. Manson Benedict Thomas H. pisford Hans Wolfgang Levi CONTENTS Preface Chapter 1 Chemical Engineering Aspects of Nuclear Power Introduction Nuclear Fission Nuclear Fuels Nuclear Reactor Types Fuel Processing Flow Sheets Fuel-Cycle Operations Fuel Reprocessing lsotope Separation Nuclear Fusion References Problems Chapter 2 Nuclear Reactions 1 Nuclides 2 Radioactivity 3 Decaychains 4 Neutron Reactions 5 The Fission Process 6 7 Growth and Decay of Nuclides with Simultaneous Radioactive Decay, Neutron Absorption, and Continuous Processing Derivation of the Bateman Equation (2.17) by Laplace Transforms Nomenclature References Problems Chapter 3 Fuel Cycles for Nuclear Reactors 1 Nuclear Fuels 2 Effects of Irradiation on Nuclear Fuels 3 Fuel and Poison Management Xiii 1 1 2 5 7 10 15 20 22 23 24 25 26 26 27 35 42 53 63 76 78 80 81 84 84 87 90 .iii CONTENTS 4 5 6 7 Chapter 4 1 2 3 4 5 6 7 Chapter 5 1 2 3 4 5 6 7 8 9 10 Chapter 6 1 2 3 4 5 6 7 8 9 10 Chapter 7 1 2 Fuel Management in a Large Pressurized-Water Reactor Fuel-Cycle Costs Hand Calculation of Fuel-Cycle Performance Fuel-Cycle hiaterial Flow Sheets Nomenclature References Problems Solvent Extraction of Metals Applications Extractable Metal-Organic Complexes Solvent Extraction Principles Distribution Coefficients Solvent Requirements Theory of Countercurrent Equilibrium Extraction Solvent Extraction Equipment Nomenclature References Problems Uranium Uranium Isotopes Uranium Radioactive Decay Series Metallic Uranium Uranium Compounds Uranium Solution Chemistry Sources of Uranium Uranium Resource Estimates Concentration of Uranium Uranium Refining Production of Uranium Metal References Problems Thorium Uses of Thorium Thorium isotopes Thorium Radioactivity Metallic Thorium Thorium Compounds Thorium Solution Chemistry Thorium Resources Concentration and Extraction of Thorium Purification of Thorium Conversion of Thorium Nitrate to Oxide, Fluoride, Chloride, or Metal References Problems Zirconium and Hafnium Uses of Zirconium and Hafnium Natural Occurrence 105 113 126 144 151 153 154 157 157 157 160 165 172 173 198 21 1 212 214 216 21 6 217 222 223 229 232 234 236 266 274 280 28 1 283 283 283 285 287 289 293 294 298 30 7 309 315 317 318 318 319 CONTENTS ix Chapter 8 1 2 3 4 5 Chapter 9 1 2 3 4 5 6 Chapter 10 1 2 3 4 5 6 7 8 Chapter 11 1 2 3 4 5 Production and Rice Zirconium and Hafnium Metal and Alloys Zirconium and Hafnium Compounds Extraction of Zirconium and Hafnium from Zircon Separation of Zirconium and Hafnium Production of Metallic Zirconium and Hafnium Alternatives for Producing Hafnium-Free Zirconium from Zircon References Problems Properties of Irradiated Fuel and Other Reactor Materials Fission-Product Radioactivity Radioactivity of the Actinides Effect of Fuel-Cycle Alternatives on Properties of Irradiated Fuel Radioactivity from Neutron Activation Neutron Activity in Recycled Fuel Nomenclature References Problems Plutonium and Other Actinide Elements General Chemical Properties of the Actinides Properties of Protactinium Properties of Neptunium Properties of Plutonium Properties of Americium Properties of Curium References Problems Fuel Reprocessing Objectives of Reprocessing Composition of Irradiated Fuel History of Reprocessing The Purex Process Reprocessing Thorium-Based Fuels Reprocessing LMFBR Fuels Neptunium Recovery in Reprocessing Prevention of Criticality in Reprocessing Plants References Problems Radioactive Waste Management Introduction High-Level Waste Non-High-Level Waste Special Radioactive Waste Disposal of Radioactive Waste 319 320 323 330 333 342 348 348 350 352 352 364 381 39 1 401 404 405 406 401 407 420 424 426 449 45 1 454 45 6 457 45 7 45 7 45 8 466 514 527 537 547 556 563 565 565 567 604 609 61 3 x CONTENTS 6 Chapter 12 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Chapter 13 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Assessment of Long-Term Safety References Problems Stable Isotopes: Uses, Separation Methods, and Separation Principles Uses of Stable Isotopes Isotope Separation Methods Terminology Stage Properties Types of Cascade The Simple Cascade The Recycle Cascade The Ideal Cascade Close-Separation Cascade Separative Capacity, Separative Work, and Separation Potential Differential Equation for Separation Potential Equilibrium Time for Isotope Separation Plants Squared-off Cascade Generalized Ideal Cascade Three-Component Isotope Separation Nomenclature References Problems Separation of Isotopes of Hydrogen and Other Light Elements Sources of Deuterium Deuterium Production Processes and Plants Separation Factors in Distillation Distillation of Hydrogen Distillation of Water Electrolysis Electrolysis and Steam-Hydrogen Exchange Separation Factors in Deuterium Exchange Processes Number of Theoretical Stages in Exchange Columns Monothermal Exchange Processes Dual-Temperature Water-Hydrogen Sulfide Exchange Process Dual-Temperature Ammonia-Hydrogen Exchange Process Methylamine-Hydrogen Exchange Processes Dual-Temperature Water-Hydrogen Exchange Processes Exchange Processes for Separation of Lithium Isotopes Exchange Processes for Other Elements Nomenclature References Problems 618 624 626 627 627 629 644 647 65 1 65 3 654 65 8 665 667 674 677 684 685 693 70 1 703 70 5 708 708 710 71 2 717 722 738 749 756 760 7 62 767 792 797 799 800 80 1 804 806 808 CONTENTS xi Chapter 14 Uranium Isotope Separation Introduction Isotopic Content of Uranium Uranium Enrichment Projects Gaseous Diffusion The Gas Centrifuge Aerodynamic Processes Mass Diffusion Thermal Diffusion Laser Isotope Separation Nomenclature References Problems Appendixes A Fundamental Physical Constants B Conversion Factors C Properties of the Nuclides D Radioactivity Concentration Limits for Selected Radionuclides 812 812 813 815 818 847 876 895 906 914 922 925 929 933 933 935 937 979 Index 983 [...]... fission reactors As isotope separation processes are of such importance in nuclear chemical engineering, they are discussed briefly in this chapter and in some detail in the last three chapters of this book 1 2 NUCLEAR CHEMICAL ENGINEERING Neutron - ) 1 Flpun 1.1 Fission of 235 Uranium235 nudeus U nucleus by neutron 2 NUCLEAR FISSION The nuclear f w o n process utilized in today's power-producing reactors... B B4 C [C21 IS11 Zircaloy B4 c [E21 CHEMICAL ENGINEERING ASPECTS OF NUCLEAR WWER 9 Steam Feed Water Pump Primary Water Pump Figure 1.8 Schematic of pressurized-water nuclear power plant is Generotor - Woter Recirculator H 2 0 Coolant Moderator + Condenser Condensote - Feed Water Pump Figure 1.9 Schematic of boiling-water nuclear power plant 10 NUCLEAR CHEMICAL ENGINEERING reactors; helium gas has... encouragement, and patience made this book possible, CHAPTER ONE CHEMICAL ENGINEERING ASPECTS OF NUCLEAR POWER 1 INTRODUCTION The production of power from controlled nuclear fission of heavy elements is the most important technical application of nuclear reactions at the present time This is so because the world’s reserves of energy in the nuclear fuels uranium and thorium greatly exceed the energy reserves... This chapter gives a brief account of the nuclear fusion reaction and the most important f d l e fuels It continues with a short description of a typical nuclear power plant and outlines the characteristics of the principal reactor types proposed for nuclear power generation It sketches the principal fuel cycles for nuclear power plants and points out the chemical engineering processes needed to make these... -7520, 29 1-388 1968, especially pp CHEMICAL ENGINEERING ASPECTS OF NUCLEAR POWER 25 B1 Bettis, E S , and R C Robertson: “The Design and Performance Features of a Single-Fluid Molten-Salt Breeder Reactor,” NucL AppL Tech 8:190 (1970) C1 “CANDU-Douglas Point Nuclear Power Station,” NucL Eng 9:289 (1964) C2 Central Electricity Generation Board, London: “Dungeness B AGR Nuclear Power Station,” Report NF-15473,... highest temperature, around 3W°C (572'F), to which it is heated in the reactor The main difference in principle from Fig 1.7 is 8 NUCLEAR CHEMICAL ENGINEERING Steom Coolant Genera tor Steom Condenser Condensote Preheater Feed Woter pump Coolont Circulotor Figure 1.7 Schematic of nuclear power plant with separate fuel, moderator, and coolant that there is no separation of coolant from moderator in the reactor... chemical engineering processes, including isotope separation, separation of metals by solvent extraction, and the separation and purification of intensely radioactive materials on a large scale This text is concerned primarily with methods for producing the special materials used in nuclear fission reactors and with processes for separating isotopes and reclaiming radioactive fuel discharged from nuclear. .. discharged include deterioration of cladding as a result of fuel swelling, thermal stresses or corrosion, and loss of nuclear reactivity Figure 1.16 Gaseous diffusion plant of U.S Department of Energy, Oak Ridge, Tennessee, (Courtesy of US.Atomic Energy Commission.) CHEMICAL ENGINEERING ASPECTS OF NUCLEAR POWER 19 Figure 1.17 Purex plant of U.S Department of Energy, Hanford, Washington (Courtesy of Atlantic... aqueous phase, while uranium remains in the solvent Solvent from contactor I1 is fed to one end of contactor 111, which is stripped at 22 NUCLEAR CHEMICAL ENGINEERING the other end by water, which transfers the uranium to the aqueous phase leaving the contact or After chemical treatment to remove degradation products, the solvent leaving contactor In is reused in contactors I and 11 This brief discussion... SEPARATION Although the isotopes of an element have very similar chemical properties, they behave as completely different substances in nuclear reactions Consequently, the separation of isotopes of certain elements, notably 235U from =U and deuterium from hydrogen, is of great importance in nuclear technology Table 1.5 lists isotopes important in nuclear power applications, together with their natural abundance . Publication Data Benedict, Manson Nuclear chemical engineering, (McGraw-Hill series in nuclear engineering) Includes bibliographies and index. 1. Nuclear engineering. 2. Nuclear chemistry. I. Pigford,. NUCLEAR CHEMICAL ENGINEERING Second Edition Manson Benedict Professor Emeritus of Nuclear Engineering Massachusetts Institute of Technology Thomas H. Pigford Professor of Nuclear. Hans Wolfgang Levi CONTENTS Preface Chapter 1 Chemical Engineering Aspects of Nuclear Power Introduction Nuclear Fission Nuclear Fuels Nuclear Reactor Types Fuel Processing Flow Sheets